PTSD is not Tumblr-fairy disease; it's the thing you get from being interned in a POW camp or locked in someone's sex dungeon for months/years. People do have a right to avoid reliving that sort of experience.
Which, like I said, might mean that they'd have to avoid going to university altogether. It's probably nearly impossible to have an environment that both allows for a free-flowing exchange of ideas, and yet protects people with this sort of permanent mental disability.
But making an allowance for rape survivors to leave the room when there's going to be a live screening of Salò isn't all that hard, is it?